Constraints on the SCEC 3D Velocity Model: 2D Gravity Modeling of the Transverse Ranges
Nancy Natek
Univ. of New Mexico
natek@unm.edu
Mentor: Mousomi Roy
Gravity can be a useful tool in
constraining seismic tomography. In this project we develop a
2D gravity model based on version 2 of the Southern California
Earthquake Center (SCEC) 3D velocity model to constrain the tomographic
model. The 3D seismic velocity model for Southern California in
the Los Angeles region is a crustal tomographic model of P-wave
and S-wave velocities reflecting density structures. This study
is based on previous work by Roy and Clayton for version 1 of
the SCEC 3D velocity model which showed that the seismic tomography
was in general consistent with gravity but with some discrepancies
in the LA Basin and Transverse Ranges. In the preliminary part
of our study shown in the slides below, we compare four 2D topographic
profiles across the central and eastern Transverse Ranges to Airy
Compensation models and observed gravity. In our current research
we are using scaling relations of Vp and density to calculate
the crustal density variations from the SCEC 3D velocity model
and comparing the observed gravity to the predicted gravity.
Table of Contents
Constraints on the SCEC 3D Velocity Model: 2D Gravity Modeling of the Transverse Ranges
Profile 1 (delrho=500, crust=2800, mantle=3300)
Profile 2 (delrho=500, crust=2800, mantle=3300)
Profile 3 (delrho=500, crust=2800, mantle=3300)
Profile 4 (delrho=500, crust=2800, mantle=3300)